Boosting anaerobic digestion performance by exogenous carbon dioxide bioconversion: lab-scale, pilot-scale and microbial study on sewage sludge and municipal solid waste units
A novel strategy for enhancing anaerobic digestion (AD) by converting carbon dioxide (CO2) into methane (CH4) without addition of exogenous hydrogen (H2) was investigated.Proof of concept at laboratory scale for sewage sludge and municipal solid waste (MSW) ADs is presented,as well as performance increase in continuous pilot scale ADs treating MSW (> 225 days of operation) and sewage sludge (> 130 days of operation).Pathways of CO2 utilisation were also investigated by microbial community analysis and monitoring of H2 concentration in pilot scale units.A substrate dependant response to exogenous CO2 was obtained in laboratory units,with 2.1-2.4 specific CH4 production increases in sewage sludge units and ca.1.13 fold for MSW.A specific CH4 production increase of ca.20% and 12% in MSW and sewage sludge continuous pilot scale ADs,respectively,was recorded.A higher resilience of the ADs enriched with CO2 against process disturbances (temperature drop and temporary overloads) was observed.An up to 80% increased Methanosaetaceae activity and a 2.5 fold increase in H2 gas concentration were recorded in ADs periodically enriched with CO2.Homoacetogenesis (via Wood-Ljungdahl pathway) followed by acetoclastic methanogenesis is proposed as a mechanism for exogenous CO2 utilisation.Current on-going work is aimed at increasing readiness for full scale implementation,which is been done in collaboration with the UK water industry.
Carbon dioxide anaerobic digestion sewage sludge municipal solid waste hydrogen methanogens
Y.Bajón Fernández A.Soares P.Vale L.Alibardi K.Koch E.Cartmell
Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK Severn Trent Water, 2 St Johns Street, Coventry, CV1 2LZ, UK Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany
国际会议
The 15th IWA World Conference on Anaerobic Digestion( 第15届IWA世界厌氧大会)
北京
英文
669-672
2017-10-17（万方平台首次上网日期，不代表论文的发表时间）